Cong trinh Khoa hqc
M Q T LU'aC DO GIAU TIN MOfI DU'A TREN KHAI TRIEN QR
CAO THI LUYEN NGUVfiN KIM SAO
Trudng Bgi hgc Giao Ihong Van tdi B O I T H ! H 6 N G NHUNG Hgc vien Ngdn hdng
Tom lat: Vi^c nghien ciru cdc phuang phdp phdn tich ma trgn de irng dung trong linh vuc gidu tm vd thuy vdn nhdm ndng cao khd ndng nhdng, tdng cudng chdt luang dnh chua tin hay cdi thien linh bdo mgt dugc nhieu hgc gid quan tdm. Mpt trong nhirng cdch tiep cdn hieu qud td su ditng cdc phep biin doi ma trdn. vi du QR. SVD... Trong bdi bdo ndy, chung tdi de xudt mpt luge gidu tin dira vdo phep khai tnen QR Thuc nghiim cho thdy. luge do de xudt Idiong chi CO khd nang nhung cao han md cdn cho chdt luang dnh lot so v&i cdc Iuac do liin quan.
Han nira, luge dd di xudt cUng bin vitng han Irudc mpt so phep tdn cong nhu nen JPEG, thim nhieu. lgc vd ldm md.
Summary: Analyzing matrix methods fo improve the capacity and enhance the quality of data hiding applications and watermarking have been concerned by many researchers. An efficient approach is to use matrix transformations. In this paper, we propose a new data hldlngscheme based on the QR decompositlonin order to achlevea higher capacity Experiments showed that, in comparision with several relaiedschemes, the proposed scheme is not only obtalna higher capacity, but also good Image quality Besides, the proposed scheme is more robust against some delibaraled attacks as JPEG compression, adding noise, filtering and blurring
I. T 6 N G QUAN
Hien nay, vific nhiing thfing tin vao trong mgt dfii tugng (vi du mpt bdc anh) de truyen di tren mgng la phfi bien. Viec nhiing tin nay nhdm muc dich bao mat thong tin cdn gidu (gidu tin mat - steganography) hoac dk xdc thuc hoac bao ve ban quyen cho mfit dfii lugng sfi ma nfi nhung vdo (thiiy vdn - watermarking). Gidu tin mat vd thuy vdn dlu sd dung cfing cu la luge dfi gidu tin. Vi^c gidu tin cd thi dugc thuc hien tren miln khfing gian anh hodc miln biln dfii ciia anh nhd cac phep biln ddi: DCT [9,10], SVD [5,6], QR [1-4], DWT [8]... Trong bai bao nay, chiing tfii nghien cdu luge dfi gidu tin ciia anh sfi tren miln biln dfii QR Huong nghien cdu chinh ciia cac luge dfi nhiing tin dua tren khai trien QR[l-4] la thyc hien nhiing mpt bit dd lieu vdo ma trdn Q [4] hoac nhiing dd lieu trSn ma trdn R[l] hay ket hgp phuang phap QR vdi cdc phep biln dfii khdc nhu DCT, DWT [2,3]. Qua khao sat cho thdy cac he sfi d hang 1 ciia ma trdn R la tuong dfii dfing dlu nhau vl gia trj tuyet dfii, vi vgy chimg tfii Idy hai cap {R(I,1), R(l,2)}
vd {R(l,3). R(l,4)} de tien hdnh nhiing hai bit dd lieu. Do dfi, luge dfi nhimg tin de xudt cfi kha ndng nhiing cao hon so vdi mot sfi lupc-dfi gidu tin sd dung QR [ 1 -4]. Thuc nghifim cung chdng to lupc dfi de xuat khong chi cho chdt lugng anh tfit md cdn ben vung hon cac luge QRl va
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QRN dugc do xudt dong [1] trudc mpt sfi phep tdn cfing biln dfii dnh. Phdn tilp theo cda bai bao dugc bd cue nhu sau: Muc 2 la mgt so lain thiic ca .so vi khai triin QR va cdc lugrc do lien quan. Luge do nhiing tin di xudt dugc trinh bdy a Muc 3. Myc 4 la kit qud thir nghiim so sdnh luge dd di xudt v&i luge do QRl vd QRN ve chdt lircmv dnh ciing nhu do bin vOng. Cuoi ciing la kit lugn cua bdi bdo dugc trinh bdy a Muc 5.
II. MOT SO KIEN THlTC CO SO 2.1. Khai triln QR
Mpi ma tr^n thuc A cdp m^n cho dudc dlu co thi phdn tich thanh ttch ciia 2 ma dan thuc nhu sau [7, trang 223]:
A = QxR
Trong dd: Q Id ma trgn true chuan cap mxm; R la ma trgn tam giac den cap m^n.
13.. Lirgc do QRl
Gid sd can nhiing s hit B = (b|, ...,bs) vao dnh gfic 1 vdi h? sfi lupng td q(q > 0, q € R) de nhdn dugc anh I chda ddu thuy van B. Luge dfi ndy thue hien nhung I bit vaophan tu R(l,l) ciia ma trdn R, bao gom qua trinh nhiing thuy van va kiem tra dau thuy van chi tiet nhu sau:
2.2.1 Qud trinh nhiing gidu thiiy vdn
, Budc I: Chia dnh I thdnh t khoi khdng giao nhau timg dfii mpt va cd cimg kich thudc m^n, kyhieu la l „ i = I, 2,... ,t(t>s).
Budc 2: Ap dyng phan tich QR tren mdi khfii 1,:
l,= Q,^R,
Budc 3: Nhung bit b| vdo phdn tuR,( 1,1) ciia ma trdn tam gidc tren R,.
Budc 3.1: Tinh:
• R , ( M ) | q J Budc 3.2: Dilu chinh R,(l,l) thanh R, (1,1):
R;(l,l) = k, xq-(-((k,mod2)XORb,)><q
Budc 4: Tinh l| = Q, x R^, anh l' tgo tu cac khfii I,' la dnh chda ddu thiiy van B.
2.2.2 Qud trinh kiim tra gidu thuy vdn
Gia sd anh I bj tdn cfing trd thdnh anh l', thudt todn dudi ddy se kilm tra su tfin tgi ciia ddu thuy vdn trong anh 1* dl kit lugn vl ban quyin dfii vdi 1* ciia tdc gid cfi anh I.
Budc I: Chia anh T thanh t khfii nhu trong thudt todn nhiing thiiy van, ky hieu la 1,*, i=l,...,t.
9 4 Tgp chi KHOA HQC GIAO THONG V ^ N TAI So 48 - 10/2015
Cong trinh Khoa hq^
Budc 2: Ap dung phan tich QR cho timg khfii l,':
1,' = Q,' X R,' Budc 3: Xdc djnh bit b,*tdR,'(l,l) nhu sau:
R'(l,l)+'^
'^ ^ 2
Budc 4: So sanh ddu thuy vdn B" =(b',...,b*) trich ra td 1* vdi ddu thiiy van gfic B = (b,,.-,bj)bdng cdch diing he sd Err:
ErT = - y b XORb" (2.2)
H$ sfi Err dugc so sanh vdi nguong T ^ [0,1], neu Err <T (tdc Id B* kha gan vdi B) thi kit lugn anh I'cfi nhiing ddu thuy vdn B va anh I* vdn thupc vl tdc gia cfi dnh I. H$ sfi ndy se dugc dimg de danh gid do ben viing ciia luge dfi dong Muc 4.
2.3. Lirgc do QRN
Luge dfi QRN tuong tu nhu luge dfi QRl chi khac d chfi: dl nhiing 1 bit thi luge dfi QRl dua vdo phdn td R(l,l) dong khi luge dfi QRN dua vdo tdt cd khac phdn td d hang 1 ciia ma trdn R. Cac budc trong quy trinh nhiing vd kiem tra ddu thiiy van cua luge dfi QRN tuong tu nhu luge dfi QRl chi khdc d budc 3:
Bu-dc 3 dfii vdi quy trinh nhung tin:
Nhung bit b, vdo phdn tu R,(l,l), ),R,(l,2),...,R,(l,n)
Xi=R,(l,l)+R,(l,2)+...+R,(l,n);k, = p - ;x; =k, xq+((k, M0D2)©b,)xq
Dieu chinh R, thdnh R,': R(IJ)' =-=-R(l,j) B u ^ 3 ddi vdi quy trinh kiem tra dau thuy van:
Tinh: x; = R;(l,l)+R;(l,2) + ...+ R ; ( l . n ) ; | ( ' - ' ^
Trich tin: = lc M0D2
Nhan thSy cic phSn tir a hang' I cua ma tran R CO dp Ion tucmg d6i dong 6ku ve gia tri tuyet d6i. Do v|y co the dira vao tong cua 2 cap phan tCr iien tiep de nhung 2 bit de tang Icha nang Tjp chi KHOA HOC GIAO THONG VAN TAI So 4 8 - 10/2015
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Cong trinh Khoa hoc
nhung. Phdn tilp theo se dl xudt luge do nhiing hai bit dya vdo cap {R(l,l), R(l,2)} va cap {R(1,3)&R(1,4)}.
III. LU'aC DO NHUNG TIN DE XUAT 3.1, Quy trinh nhiing tin
Budc 1: Chia dnh I thanh t khfii khfing giao nhau tdng dfii mot va cfi cung kich thudc m^n, kyhieu la l „ i = 1,2, ...,t.
Budc 2: Ap dung phan tich QR tren mfii khfii 1,, i = 1,2, ...,t.
l,= Q,xR,
Budc 3: Nhiing bit b, vao cap phdn td {R|(I,1),R|(2,1)} va bit b,4^i vao cap phan tir {Ri(3,l),R,(4,l)}cua ma trdn Ri. Dudi day trinh bay viec nhimg b vao cgp phdn td {R,(l,l),R,(2,l)}:
xn=R,(l,l)+Ri(l,2); k i | = h ^ ; x', =k„ xq + ({k„ MOD2)ffib,)xq
Dieu chinh R, thanh R,'; Raj);-^R,(ij)j=i,2
Viec nhiing bit b^-i vao cap phan tu {R|(3,l),R|(4,l)} dugc thuc hien tuong tu.
Budc 4: Tinh Ij = Q, x R|, anh 1 tao tu cac khfii I, la anh chda dau thiiy van W.
3.2. Quy trinh trich tin
Budc 1: Chia anh l' thdnh t khfii nhu trong thudt todn nhiing thiiy van, ky hieu Id I,',
Budc 2: Ap dyng phdn tich QR cho tdng khfii I, : I,* = Q,* x R,*
Budc 3: Trich b,vd b,*! nhu sau:
X : , = R : ( I , I ) + R : ( I , 2 ) . k'- b, - k , M 0 D 2 ; x ; , - R ; ( 1 , 3 ) + R ; ( 1 , 4 ) ;
b* = k ' ' M 0 D 2
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Tap chi KHOA HQC GIAO THONG VAN TAI So 48 - 10/2015Cong trinh Khoa hqc
IV. KET QUA THU" NGHIEM
Ophdn ndy, chimg tfii sudung cac anh chudn (a),(b),(c)ca 512x512 lam anh gfic vaanh nhi phan (d) kich thdc 30x30 ldm dd lieu mat nhu hinh 1 dudi ddy:
Hinh I. Anh goc (a) "Lena", (b) "Boat", (c) "Cactus" vd dnh nhitng 30x30 (d) "UTC"
Ddu tien anh gfic (c) se dupc nhiing anh (d) de dugc anh chda tin. Sau do thuc hien thii tuc tri'ch tin td anh chda tin do. Ket qua nhdn dugc chi'nh Id anh (d) da nhiing. Nhu vdy luge dfi de xudt Id dimg ddn vi riit trich dugc diing dnh da nhiing vdo anh gfic. Quy trinh thd nghiem nhimg vd trich tin dugc mfi td trong hinh 2 dudi ddy:
Hinh 2. Qud trinh ihu nghiem nhung vd trich dn 4.1. Ve dd b€n v ^ g
Chiing tfii sd dyng h? sfi Err (muc 2.2) de khao sdt dfi ben vdng ciia cac luge dfi qua cdc phep tdn cfing them nhieu 5%, lam md 3%, them bong, nen Jpeg 70%. Luge dfi nao cfi Err nho han se cfi dp bin vdng tfit hon.
Tgp chi K H O A H Q C G I A O T H O N G VAN TAI So 48 - 10/2015
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Cong trinh Khoa hoc
Cac phep tan cong
Them nhieu
Lam met
Them bdng
Nen Jpeg
Lpc trung binh
- Cac lirffc do Luge d6 QRl Luge d6 QRN Luoc do de xuat Luyc d6 QRl Luyc d6 QRN Luge do de xuat Luge da QRl Luge de QRN Luge do de xuat Luge d6 QRl Luge d6 QRN Luge do de xuat Luge d6 QRl Luge de QRN Luge de de xuat
Anh Lena 0.0853 0.0794 0.0784 0.4265 0.4245 0.1480 0.5893 0.5873 0.2471 0.2990 0.2996 0.1324 0.4902 0.4302 0.2088
Bang J. Err cita cdc iuac di Anh Boat
0.0863 0.0814 0.0716 0.3667 0.2225 0.1422 0.6137 0.2618 0.2520 0.2745 0.3431 0.1412 0.4382 0.2270 0.1824
Anh Cactus 0.0873 0.0765 0.0716 0.4216 0.3275 0.1422 0.5 0.3412 0.3412 0.2725 0.1637 0.1412 0.4314 0.3549 0.1824 4.2. V£ chat lirgng anh
De danh gia chat tugng anh ciia cdc luge dd, chiing tfii sd dung he sfi PSNR, PSNR dugc tinh nhu mue 4.1 trong [4]. Luge dfi nao cfi PSNR cao hon dugc danh gia la cd chat lugng anh tdt hon.
Bdng 2. PSNR cua cdc luge do Lirgc do
Luge de QRl Luge de QRN Luge de d6 xu^t
Anh Lena 54.7292 54.8753 54.6538
Anh Boat 51.0742 52.3054 51.3099
Anh Cuctus 50.9574 52.1791 51.4976 TCr bang 1 cho thiy, cac luge d6 co chit lugng anh tdt va tuong duong nhau.
V. KET LUAN
Bai bao de xu4t luge dd giiu tin mdi dua tren khai tri^n QR. Trong luge d6 de xuit, hai bit do lieu duge nhung vao hai cip {R(l,l), R(l,2)} va {R(I,3), R(l,4)) thay vi nhUng mgt bit dua vao R(l) nhu met se luge d6 quen thugc dua tr6n phan tich QR. Nhd vay m^ lirac dd d6 xuit co
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Tap chi KHOA HQC GIAO THONG VAN TAI So 48 - 10/2015Cong trinh Khoa hqc
khd ndng nhung cao hon. Thuc nghiem cung chung tfi luge do de xudt cd dp ben vifng cao hon trudc cdc phep tdn cfing them nhilu, lam md, Ipc trung binh, nen Jpeg, them bdng so vdi mfit sfi luge dfi dya trdn biln dfii QR.
Ngay nhan bdi ldn ddu: 28/9/201S Ngay nhan bai sua: 27/11/2015 Ngay ch^p nhdn dang bai: 30/10/2015
Tai li^u tham khao
[1]. Trdn Ddng Hien, Do Vdn Tudn, Nguyen Ngpc Hung vd Phgm Vdn At "Mot lupc dl thiiy van mai dya tren phan tich QR", Tap chi khoa hoc cong ngh? cua Bo thfing tin va truyln thong, nam 2014.
[2]. H. Chen and Y. Zhu, "A robust watermarking algorithm based on QR factorization and DCT using quantization index modulation technique", Joumal of Zhejiang University Science C, pp. 573-584,2012.
[3]. K Naderahmadian and H.K Saled, "Fast watermarking based on QR decomposition in wavelet domain",Intelligent Information Hiding and Multimedia Signal Processing (IIH-MSP), 2010 Sixth Intemational Conference on. IEEE, 2010.
[4]. fV Song, H. Jian -Jun, H. Ll and L. Huang, "HouChaotic system and QR factorization based robust digital image watermarking algorithm robust digital image watermarking algorithm",J. Cent. South Univ.
Technol.pp 116-124,2010.
[5]. R. Sun, H. Sun and T. Yao, "A SVD and quantization based semi-fragile watermarking technique for image authentication", Proc. Internat. Conf. Signal Process. 2, pp. 1952-1955, 2002.
[6]. X. Sun, J. Liu, J. Sun. Q Zhang and W. Ji, "A robust image watermarking scheme based on the relationship of SVD", in Proc. Int. Conf Intelligent Information Hiding and Multimedia Signal Processing (IIHMSP '08), Harbin, pp. 731-734, August 2008.
[7]. G.H Golub and C.F.V. Loan, "Matrix Computations", third ed., Johns Hopkins University Press, Baltimore MD, 1996.
[8]. S. Lee, C. D. Yoo and T. Kalker, "Reversible image watermarking based on integer-to-integer wavelet transform," IEEE Transactions on Information Forensics and Security, vol.2, issue3, part 1, pp. 321-330, September 2007.
[9]. l.J.Cox. J.Kilian. T.Leighton and T.Shamoon, "Secure spread spectrum watermarking for images, audio and video", Proc IEEE Internat. Conf on Image Processing (ICIP'96) Vol, III, Lausanne, Swizerland, pp. 243-246, September 1996.
[10], R.Munir, B.Rlyanto, S. Sutl'kno and W.P. Agung, "Derivation of Barni Algorithm into Its Asymmetric WatermarkingTechnique Using Statistical Approach",Intemational Joumal on Electrical Engineering and Informatics- Volume 1, Number 2,2009*
Phan bi?n: TS. Nguyen Hieu Cudng; TS. Nguyen Tr9ng Phiic
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